How to use the van t hoff equilibrium constant change calculator
Estimate how an equilibrium constant changes with temperature from the reaction enthalpy. Enter equilibrium constant at t1, temperature 1, temperature 2, enthalpy of reaction in the fields above; the equilibrium constant at t2, change factor are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “van t Hoff equation”, “equilibrium constant at new temperature”, “temperature effect on K”, “calculate van t hoff equilibrium constant change”, “find equilibrium constant at t2”.
Formula
Variables
- K1 — Equilibrium constant at T1
- T1 — Temperature 1 (K)
- T2 — Temperature 2 (K)
- dH — Enthalpy of reaction (kJ/mol)
Worked example
With equilibrium constant at t1 = 2, temperature 1 = 298.15 K, temperature 2 = 350 K, enthalpy of reaction = 30 kJ/mol, the calculator gives equilibrium constant at t2 ≈ 12.01255; change factor ≈ 6.006274 ×.
Frequently asked questions
What is the van t hoff equilibrium constant change calculator used for?
Estimate how an equilibrium constant changes with temperature from the reaction enthalpy. It helps with questions such as “van t Hoff equation”, “equilibrium constant at new temperature”, “temperature effect on K”.
What is the formula for the van t hoff equilibrium constant change calculation?
Equilibrium constant at T2 = K1 × exp(-dH × 1000 / RGAS × (1 / T2-1 / T1)). Change factor (×) = [Equilibrium constant at T2] / K1. Here K1 is equilibrium constant at t1, T1 is temperature 1 (K), T2 is temperature 2 (K), dH is enthalpy of reaction (kJ/mol).
What inputs do I need for the van t hoff equilibrium constant change calculator?
You need equilibrium constant at t1, temperature 1 in K, temperature 2 in K, enthalpy of reaction in kJ/mol. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the van t hoff equilibrium constant change calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the van t hoff equilibrium constant change result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.